dramatic story today told by people at the center during that attack in benghazi last year, people who said they were pleading for help. As you know, four americans, including the ambassador died and abc's chief white house correspondent, jonathan karl, has more on what we learned today. Reporter: They are the benghazi whistle-blowers. Today three three foreign service officers told their side of the story. None of us should ever again experience what we went through in tripoli and benghazi. Reporter: Gregory hicks was chris stevens' deputy. He recounted talking to the ambassador shortly after the attack began, likely the last american to speak to him. I got the ambassador on the other end. He said, greg, we're under attack. Reporter: The line cut out and hicks at the embassy in tripoli scrambled to get help. He wanted to send a special forces team, but the team was ordered to stand down. How did the personn react to being told to stand down? They were furious. Reporter: The pentagon said the team was needed to secure the embassy in tripoli and would not have gotten to benghazi in time to help. Several hours after talking to the ambassador, hicks received another call. I think it's the saddest phone call I've ever had in my life. And he told me that ambassador stevens had passed away. Reporter: While none of the whistle-blowers placed direct blame on then secretary of state hill' clinton, one of them took issue with what she said earlier this year when she testified about the administrations initial portrayal of a protest gone bad. It turned out not to be true. Whether it was a protest, or guys out for a walk to kill americans, what difference at this point does it make? What happens prior, during, and after the attack, matter. And it matters to my colleagues -- to my colleagues at the department of state. Reporter: While today's hearing provided a dramatic personal account of what happened in libya during the attack, republicans say it also shows how politics play a roll in how the administration responded. Something the white house flatly denies. Jonathan karl, thank you. Now we taurn to your helt

This transcript has been automatically generated and may not be 100% accurate.

Benghazi Hearing: Gregory Hicks Describes Consulate Attack

House Oversight Committee seeks to determine if Libya attack could have been prevented.

{"id":19137944,"title":"Diplomat Raises New Alarm on Benghazi","duration":"2:22","description":"Insiders at the State Department say not enough was done during the attack that killed four American","section":"WNT","mediaType":"Default"}